Noise-eliminating means for selfwinding electric clocks



p 3, 1964 J. L. HANCOCK 3,148,313

NOISE-ELIMINATING MEANS FOR SELF-WINDING ELECTRIC CLOCKS Filed Aug. 3,1962 1:ui lllllllll l 14, 28 mama/9770 INVENTOR. I.

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United States Patent 3,148,313 NOISE-ELIMINATING MEANS FOR SELF- WINDINGELECTREC CLOCKS John L. Hancock, Chicago, Ill., assignor, by mesneassignments, to Amphenol-Borg Eiectronics Corporation,

Broadview, 111., a corporation of Deiaware Filed Aug. 3, 1962, Ser. No.214,733 1 Claim. (Cl. 317-195) My invention relates to noise-dampeningmeans for selfwinding electric clocks.

Heretofore in electric clocks utilizing an armature of anelectromagnetic coil acting upon a fly wheel by engagement of thecontact carried by the latter, for driving the fly wheel inspring-winding direction, the striking of the armature against the frameof the field coil produces upon each stroke of the armature an annoyingnoise of Sulficient volume to be head. One of the objects of thisinvention is to substantially dampen such noise, thus to provide aself-winding electric clock which is quiet in operation.

Another and equally important object is to provide an arrangement foraccomplishing the foregoing object which is relatively simple, positivein operation and economical in manufacture.

Yet another and equally important object of the invention is to providea simple and effective arrangement for separating the engagement betweenthe contact carried by the armature of an electric clock and the contactcarried by the fly wheel at a critical point in the operation of thelatter whereby to eliminate locking of the two contacts.

Other objects will appear hereinafter.

The invention consists in the novel combination and arrangement of partsto be hereinafter described and claimed.

The invention will be best understood by reference to the accompanyingdrawings showing the preferred form of construction, and in which:

FIG. 1 is a perspective view of an electric self-winding clock showingthe invention associated therewith;

FIG. 2 is an elevational view of the same;

FIG. 3 is a fragmentary elevational view similar to FIG. 2, but showingcertain parts thereof in different posi tions;

FIG. 4 is a fragmentary sectional detail view taken substantially online 44 of FIG. 2.

I prefer to accomplish the several objects of this invention by thepreferred form of construction as seen in the drawings and hereinafterdescribed. In such drawings I have illustrated only so much of theelectric self-winding clock as is necessary for an understanding of thisinvention.

The self-winding clock includes a back plate It on which the clock works11 is mounted. In the illustration shown in the drawings, this clockworks, includes, among other elements, a segmental fly wheel 12, theshaft 13 of which is journaled in one end portion 14 of a bracket 15.The fly wheel 12 has an extension to provide an arm 16. This arm 16 hasa laterally extending lug 17 which carries a contact 19.

Mounted on this plate is an electromagnetic element 20 comprising aframe 21 carrying a field coil 22. The lower bar 23 of the frame 21 haspivotally connected thereto in a manner well known in the art anarmature 24. The upper end portion of this armature 24 terminates intoan arm 25 which carries at its outer end portion 25' a contact 26adapted to engage the hereinbefore referred to contact 19 whereby tocomplete the circuit 20' between the field coil 22 and a source of power(not shown). Fixed to the outer end portion 25 by means of the contact26 which is riveted to the arm 25, is an elongated relatively fiat plate27 formed of non-conductive material. This plate 27 has an opening 28through 3,148,313 Patented Sept. 8,, 1964 which the contact 26 isexposed for engagement with the contact 19.

Upon engagement of the contact 26 with the contact '19, the field coil22 will be energized and will cause the spring-winding direction withoutproducing any undesirable noise.

The relationship of the contacts 19 and 26 to the nonconductive plate 27is such that when the armature is at the end of its stroke, the contacts19 and 26 being out of contact, it is impossible for the contacts tolock as frequently occurs in self-winding clocks now commercially inuse.

Normally, whenever the armature is attracted toward the core of thefield coil 22, the armature 24 will strike against the edge portion 29of the frame, resulting in a pronounced noise which is readily heard. Toovercome this objectionable feature which is present in the presentdayelectromagnetic coils of self-winding clocks, I mount between thearmature 24 and the field coil plate 30 a plurality of laminatedrelatively thin metal or plastic sheets 31 of high tensile strength andnot subject to swelling or distortion due to heat or humidity. Thesesheets 31 have their corresponding edge portions 32 connected to theplate 30 by means of screw studs 33, the outer ends of which looselyproject into enlarged openings 33' formed in the armature 24. The sheets31 are self-spaced from each other as shown in FIG. 2, when the armatureis in a starting position. Whenever the armature 24 is drawn toward thecore of the coil 22, the sheets will be pressed together and the airtherebetween expelled, to provide a noise dampener for the armature 24,which together with the dampening of the noise by the non-conductiveplate 27, provides a substantially quietly operating selfwinding clock.

The sheets 31 are preferably each of the same dimension and are each ofa length and breadth substantially the same as that of the armature 24.

As is the practice in self-winding electric clocks using anelectromagnetic coil, a coil spring 34 is employed with one end portionconnected to the lower arm 23 of the frame 21 and the opposite endportion connected to a depending finger 36 provided by the armature 24.The function of this spring 34, well-known in the art, is to return thearmature to its initial starting position each time that the field coil22 is deenergized.

To dampen noise of operation of the armature 24, I provide a wire 37 ofspring material having one end portion connected as at 38 to thearmature 34 and an opposite end portion 39 bearing against the arm 23 ofthe frame 21. The tension of this spring 37 is sufficient to cushion thereturn movement of the armature 24 without interfering with the returnof the armature by action of the spring 34.

From the foregoing description, it is apparent that I have accomplishedthe several objects of this invention by an arrangement which isrelatively simple and economical in manufacture.

While I have illustrated the improvements as being associated with anelectric self-winding clock, it is obvious that the same may have otherapplication.

While I have illustrated and described the preferred form ofconstruction for carrying my invention into effect, this is capable ofvariation and modification without departing from the spirit of theinvention. I therefore do not Wish to be limited to the precise detailsof construction set forth, but desire to avail myself of such variationsand modifications as come within the scope of the appended claim.

Having thus described my invention, what I claim as new and desire toprotect by Letters Patent is:

In combination, an electromagnetic device for a selfwinding clock, saiddevice including (a) a substantially U-shaped frame,

([2) a coil supported by and arranged in said frame,

(0) a field plate extending vertically between the end portions of thelegs of said frame in front of said coil,

((1) a relatively fiat armature having one edge portion pivotallyconnected to one of said legs and spaced from said field plate,

(e) a plurality of laminated substantially rectangularly shaped sheets,each of high tensile strength and resistant to swelling and distortiondue to changes in temperature and humidity, said sheets being arrangedin confronting relation with respect to each other between said armatureand said field plate to provide a noise-dampening means,

( and means for connecting corresponding edge portions of said sheets toan edge portion of said field plate adjacent the point of connectionbetween the armature and said one leg of said frame,

References Cited in the file of this patent UNITED'STATES PATENTS1,060,380 Thompson Apr. 29, 1913 1,226,748 Burnham May 22, 19173,046,456 Petrus July 26, 1962 FOREIGN PATENTS 606,429 France June 14,1926 965,690 Germany June 13, 1957 OTHER REFERENCES Germany(application) M 13473, printed December 13, 1956.

Germany (application) 1,069,085 printed November 12, 1959.

